ng to write twenty programs for the conversion of each MARC format (e.g. INTERMARC to UKMARC, USMARC to UKMARC etc.).

In 1977, the IFLA (International Federation of Library Associations and Institutions) published UNIMARC: Universal MARC Format, followed by a second edition in 1980 and a UNIMARC Handbook in 1983. These publications focused primarily on the cataloguing of monographs and serials, while taking into account international efforts towards the standardization of bibliographic information reflected in the ISBDs (International Standard Bibliographic Descriptions).

In the mid-1980s, UNIMARC expanded to cover documents other than monographs and serials. A new UNIMARC Manual was produced in 1987, with an updated description of UNIMARC. By this time UNIMARC had been adopted by several bibliographic agencies as their in-house format.

Developments didn't stop there. A standard for authorities files was set up in 1991, as explained on the website of IFLA in 1998: "Previously agencies had